What PISTONS?
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Joined: Jun 2004
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What PISTONS?
I'm building a 383 with 6" rods and having lloyd do my heads and cam(LE3). I keep getting ten million diff answers about what compression to go with. Lloyd has told me to get -6 to -6 cc pistons which will be around 11.5 to 12:1 compression. I want to run on 91 and not be on the line of having to retard the timing to make the car run w/o detonation. My engine builder told me to shoot for 10.3:1. How do all of you'll feel?
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Re: What PISTONS?
Listen to Lloyd..... I can't tell you how many "engine builders" who say 10.3:1 is the max are totally out to lunch.
I think that the JE line is a bit overkill where JE's budget line of SRP's will fit the bill nicely.
If you want to be safe, get a set of SRP -16cc dish pistons to run with the stock castings and you can put it at 11:1, but that is a better setup for a LE2 383 package and 11.5:1 is better for a LE3 package. To get there Ross, Lunati and Probe all make pistons in the -11 to -13cc range which will get you there pefectly.
Bret
I think that the JE line is a bit overkill where JE's budget line of SRP's will fit the bill nicely.
If you want to be safe, get a set of SRP -16cc dish pistons to run with the stock castings and you can put it at 11:1, but that is a better setup for a LE2 383 package and 11.5:1 is better for a LE3 package. To get there Ross, Lunati and Probe all make pistons in the -11 to -13cc range which will get you there pefectly.
Bret
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Re: What PISTONS?
Originally Posted by 69vette
yeah i'm going je pistons. How can you run on pump gas with that high of a compression ratio?
The LE head and CAM packages are matched up to make the most out of this....
BTW commonly Lloyd and I see too many guys who want LE3 packages with too little compression ratio.... that's the wrong way to go.
For reference.....
http://popularhotrodding.com/enginem...208PHRSherman/
JOE SHERMAN
Joe Sherman Racing Engines Santa Ana, CA
Total Score: 903.6
Average Torque: 482.0
Average Horsepower: 421.6
Peak HP: 604.1 @ 6,500 rpm
Peak TQ: 528.0 @ 5,100 rpm
Total Investment: $12,000
Cost to Duplicate: $16,000- 19,000
Dyno time prior to Qualifying: 20 pulls (this engine),
60 pulls (research mule)
Block: Motown, 4.040-inch bore
Crank: Scat, 3.560-inch stroke
Compression Ratio: 11.4:1
Bret
Last edited by SStrokerAce; Apr 3, 2005 at 10:24 PM.
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Posts: 6,518
Re: What PISTONS?
Bleeding off the pressure by when you close the valve......
The definintion of DCR is the compression ratio when the intake valve closes.... Do a search on it.
Go by the -11 to -13cc piston recomendations.... Lloyd and I have talked about this exact thing today so I have a feeling you are the customer who was worried about it.
Bret
The definintion of DCR is the compression ratio when the intake valve closes.... Do a search on it.
Go by the -11 to -13cc piston recomendations.... Lloyd and I have talked about this exact thing today so I have a feeling you are the customer who was worried about it.
Bret
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Re: What PISTONS?
Well i just want to make sure that its going to run fine w/o timing retard or detonation. I've never really herd of running that high of a compression ratio on pump gas. Do you have the part number on hand for the srp pistons you are suggesting bret?
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Re: What PISTONS?
Also today i was talking with lloyd about how much hp i should look for with dyno tuning, 58 mm tb, true duals, jet hot long tubes, ported intake..basically all the supporting mods. What is your opinion on the hp/torque range just to give me an idea. thanks for all your time
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From: Imperial, MO.
Re: What PISTONS?
man, just went through this whole ordeal. really wanted the le3 cam in a 383 stroker, but had trouble with compression issues. lloyd and bret said i need 11.5:1 or higher to run that cam, (has compression bleedoff also) but i called alot of machine shops locally here in st. louis, and they said on pump gas, u need to stay in the 10's. i ended up getting a reverse dome piston from ross. 10.6:1 compression on my 355. i don't know man, all the machine shops said stay in 10's, but i have a buddy that was running 12:1 on pump gas with no problems...but for me personally, it's not worth getting the engine together and finding out its gonna cost me 5$ a gallon to drive it..
also, combination motorsports and advanced induction said 11:1 is to high on lt1's. they said it MIGHT run on pump gas, but the engine will ping itself to death. just think about who is going to be putting the time in fixinging it, YOU or them. good luck, i'd recomend calling some local shops..
also, combination motorsports and advanced induction said 11:1 is to high on lt1's. they said it MIGHT run on pump gas, but the engine will ping itself to death. just think about who is going to be putting the time in fixinging it, YOU or them. good luck, i'd recomend calling some local shops..
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Re: What PISTONS?
Or you can ask WHO has done it...... US or THEM.. Why would anyone recomend something that is going to cause you harm... especially today when anyone with a keyboard and a semi grasp of the english language can be all up on you spouting out BS on a message board?
You have to ask yourself..... Is Lloyd recomending that I do something that will screw me over? That would not be good for business, but you getting good results and being happy with your car would be..... Which one do you think is his motivation?
Bret
You have to ask yourself..... Is Lloyd recomending that I do something that will screw me over? That would not be good for business, but you getting good results and being happy with your car would be..... Which one do you think is his motivation?
Bret
